Laser Photophysics of Mass-Selected Hard Clusters

Abstract

The new supersonic beam techniques using laser vaporization have now permitted detailed study of clusters of refractory elements. These are molecular species which offer qualitatively new challenges to theories of molecular dynamics. Aside from their size and complexity, a key new feature of these hard clusters is that electronic degrees of freedom are often as active in the molecular dynamics as vibrations. Three examples are given of these new dynamical problems: (1) the competition between photodissociation and photodetachment in mass-selected negative metal cluster ions, (2) the rate of desorption of small molecules chemisorbed on the surface of small metal clusters, and (3) photofragmentation pathways and rates of large positive carbon cluster ions.